Devices and methods for asymmetrical mul ticarrier transmission and reception

ABSTRACT

Devices and methods are disclosed which supplement a duplex frequency by providing one or more simplex frequencies and distributing data among them. Variations of the disclosed system include a server in communication with a communications device using a duplex channel. The server includes a scheduler that determines when it is no longer optimal to use the single duplex channel, and distributes data among the duplex channel and one or more simplex channels. Before sending this data, the server sends a schedule to the communications device through the duplex channel, so the communications device knows which bits of data are coming through which channels and at which times. A descheduler within the communications device receives the schedule and alerts the communications device to start receiving data on other simplex channels. The descheduler then puts the bits of data in order as they stream in across the duplex and simplex channels.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to data transmission. More specifically,the present invention relates to asymmetrical data transmission oversimplex and duplex channels.

2. BACKGROUND OF THE INVENTION

Cellular telephones are tremendously popular. It is estimated that atthe end of 2007 the total worldwide subscriber rate reached 3.3 billion.Close to 80% of the world's population enjoys mobile telephone coverage,a figure that will only increase. As cellular telephones gainpopularity, their functionality has increased also. Standard serviceincludes voice calling, caller ID, call waiting, and voice mail. Serviceproviders also offer text messaging, push mail, navigation, and even ahigh-speed internet connection directly to the telephone through the useof protocols such as those included in High Speed Packet Access (HSPA).

HSPA is a collection of wireless protocols that improve upon theperformance of existing Universal Mobile Telecommunications System(UMTS) protocols. High-Speed Downlink Packet Access (HSDPA), a standardwithin HSPA, increases data packet transfer performance by usingimproved modulation schemes. These improved schemes better utilizeexisting radio bandwidth provided by UMTS. HSDPA currently supportsdownlink speeds of 1.8, 3.6, 7.2, and 14.4 Mbit/s. Long Term Evolution(LTE) is a promising standard for the next generation (4G) of mobilebroadband networking.

Multiple-input and multiple-output (MIMO) requires the use of multipleantennas at both the transmitter and receiver. The signals from theantennas are combined to minimize errors and optimize data speed,providing better range and performance. However, the use of multipleinputs and outputs requires a device to utilize the same radio spectrumfrequency. The United States presently uses the GSM-850 and GSM-1900radio spectrum frequencies for cellular transmissions. GSM-850 uses824-849 MHz for uplink and 869-894 MHz for downlink, providing channelnumbers 128-251. GSM-1900 uses 1850-1910 MHz to uplink and 1930-1990 MHzto downlink, providing channel numbers 512-818. The MIMO concept definedin Third Generation Partnership Project Revision 7 (3GPP R7) andRevision 8 (MIMO R8), incorporated by reference herein in their entiretyinto this disclosure, requires the use of the same radio spectrumfrequency for both transmission paths. These frequencies and antennasare used in spatial multiplexing or transmission diversity modeaccording to radio conditions. This allows for multiple simultaneousdata streams, thereby increasing the data transmission rate.

MIMO R8 also requires twice the amount of antennas at both thetransmitter and the receiver locations, even though the transmissiontakes place across a single frequency band. This creates interference inthe signal, which decreases the actual gain in bandwidth created by MIMOR8. The additional signal used in MIMO R8 is another two-way transmitpath. Although MIMO R8 can have up to four transmit paths, the uplinkbandwidth is still equivalent to the downlink bandwidth, because eachadditional transmit path adds a duplex channel.

Demanding data services for individual users can exceed the capabilitiesof a single frequency carrier and/or radio path for a variety oftransmission technologies. In this case, the capacity of multiplebi-directional frequency carriers and/or radio paths are combined, or“bonded” for the single demanding user. Multiple pre-existingbi-directional transmission pairs are allocated to the demanding userand traffic is spread across them. The Federal Communications Commission(FCC) recently auctioned the 700 MHz frequency spectrum. AWS-700 uses776-794 MHz for uplink and 746-764 MHz for downlink.

As is, these transmission techniques offer useful means to boostindividual peak throughput within the capabilities of the availabletransmission technology. However, bi-directional frequency carriersand/or radio paths, and the equipment required to use them, are bestutilized if the data load and equipment capabilities are symmetrical.Unfortunately this is often not the case. Traffic for most data, audio,and video applications is heavily weighted in the downlink, server touser, direction. Roughly eight times as much data is downloaded to as isuploaded from mobile devices. The number of duplex signals available maylimit these downlink requests. Many frequency bands are not intended forand not licensed for transmission by an individual user. Currently thereare many of these frequencies available for downlink only which arebeing underutilized. Subscriber equipment, especially wireless, is alsolimited in terms of available space, power (battery life for mobiledevices) and cost. The need for subscriber equipment to simultaneouslytransmit on all bonded frequency carriers and/or radio paths istherefore an unnecessary burden from an equipment complexity, cost andpower perspective.

What is needed is a system that utilizes a downlink only channel tosupplement the bandwidth of a conventional duplex channel to distributethe data load.

SUMMARY OF THE INVENTION

The present invention supplements a duplex frequency by providing one ormore simplex frequencies and distributing a data load among them.Embodiments of the present invention include a server containing ascheduler in communication with a communications device. The serverinitially communicates with the communications device using a duplexchannel, or anchor channel. The scheduler determines when it is nolonger optimal to use the single duplex channel, and distributes dataamong the duplex channel and one or more simplex channels. Beforesending this data through multiple channels, the server must first senda schedule to the communications device, so the communications deviceknows which bits of data are coming through which channels at whichtimes. The scheduler compiles this schedule and sends it to thecommunications device through the duplex channel. A descheduler withinthe communications device receives the schedule and alerts thecommunications device to start receiving data on other simplex channels.The descheduler then puts the bits of data in order as they stream inacross the duplex and simplex channels.

Furthermore, embodiments of the present invention are not limited toHSPA, LTE, or wireless communication at all. The methods describedherein are useful for any bi-directional communications system wherethere is more traffic in one direction than the other. Embodiments ofthe present invention are not limited to improving downlink capacity, asa simplex channel could be used to improve uplink capacity. For evenmore capacity multiple simplex channels can be used alongside the duplexchannel.

In one exemplary embodiment, the present invention is a communicationsdevice comprising a memory, a descheduler on the memory, and atransceiver which communicates on a plurality of channels. An anchorchannel is used for duplex transmission and one or more simplex channelsare used to supplement one direction of the anchor channel.

In another exemplary embodiment, the present invention is anasymmetrical multicarrier communications system comprising a server, ascheduler in communication with the server, and a communications devicein communication with the server via a plurality of channels. An anchorchannel is used for a duplex transmission and one or more simplexchannels are used to supplement one direction of the anchor channel.

In yet another exemplary embodiment, the present invention is a methodof supplementing a data transmission of a duplex communicationcomprising selecting one or more simplex channels, compiling a dataschedule, sending the data schedule to a recipient through a duplexchannel, and sending the data transmission through the duplex channeland a first simplex channel. The data schedule comprises an associationof bits of data to channels in which each bit is sent.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a system utilizing asymmetrical data transmission andreception, according to an exemplary embodiment of the presentinvention.

FIG. 2A shows individual data streams that allow asymmetricalcommunication according to an exemplary embodiment of the presentinvention.

FIG. 2B shows individual data streams that allow asymmetricalcommunication based on position according to an exemplary embodiment ofthe present invention.

FIG. 3A shows a front view of a communications device for use withasymmetrical data transmission, according to an exemplary embodiment ofthe present invention.

FIG. 3B shows a view of components of a communications device, accordingto an exemplary embodiment of the present invention.

FIG. 4 shows a flowchart of a method of asymmetrical data transmission,according to an exemplary embodiment of the present invention.

FIG. 5 shows a data schedule used by a scheduler onboard a server,according to an exemplary embodiment of the present invention.

FIG. 6 shows a system utilizing asymmetrical data transmission andreception, utilizing multiple simplex channels, according to anexemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention supplements a duplex frequency by providing one ormore simplex frequencies and distributing a data load among them.Embodiments of the present invention include a server containing ascheduler in communication with a communications device. The serverinitially communicates with the communications device using a duplexchannel, or anchor channel. The scheduler determines when it is nolonger optimal to use the single duplex channel, and distributes dataamong the duplex channel and one or more simplex channels. Devicefeedback of the received data, such as level, quality, load, and variousparameter settings are used to balance the transmission across duplexand simplex radio channels. These factors may all contribute to theinitial and adapted ratio of data traffic sent on the various channels.Before sending this data through multiple channels, the server mustfirst send a schedule to the communications device, so thecommunications device knows which bits of data are coming through whichchannels at which times. The scheduler compiles this schedule and sendsit to the communications device through the duplex channel. Adescheduler within the communications device receives the schedule andalerts the communications device to start receiving data on othersimplex channels. The descheduler then puts the bits of data in order asthey stream in across the duplex and simplex channels.

Furthermore, embodiments of the present invention are not limited toHSPA, LTE, or wireless communication at all. The methods describedherein are useful for any bi-directional communications system wherethere is more traffic in one direction than the other. Embodiments ofthe present invention are not limited to improving downlink capacity, asa simplex channel could be used to improve uplink capacity. For evenmore capacity multiple simplex channels can be used alongside the duplexchannel.

“Channel,” as used herein and throughout this disclosure, refers to asingle data pipeline among a plurality. Examples of channels include,but are not limited to, a specific frequency, a single cable when manyare present, a specific radio path, a block of frequencies, a singlewideband carrier, etc.

“Duplex,” as used herein and throughout this disclosure, refers to achannel capable of bidirectional communication. Most duplex channels aresymmetrical, meaning they have equal bandwidth in each direction.

“Simplex,” as used herein and throughout this disclosure, refers to achannel capable of unidirectional communication. Most simplex channelsare set to one direction or the other, but some can switch back andforth.

“Communications device,” as used herein and throughout this disclosure,refers to any device capable of sending and receiving electronic bits ofdata. Examples of a communications device include but are not limited tomobile and land-line telephones, computers, personal digital assistants(PDAs), two-way radios, walkie-talkies, satellite transceivers, etc.

FIG. 1 shows a system utilizing asymmetrical data transmission andreception, according to an exemplary embodiment of the presentinvention. In this embodiment, the system comprises a wirelesscommunications device 100, a carrier antenna 110, a secondary antenna116, a server 112, and a scheduler 114. Wireless communications device100 is in communication with server 112 through carrier antenna 110 aswell as secondary antenna 116. Carrier antenna 110 is used to transmitand receive information, in form of user plain data, across a duplexchannel 120 between server 112 and communications device 110. Duplexchannel 120, or anchor channel 120, allows for two-way communicationusing the same frequency. Secondary antenna 116 transmits information,in form of user plain data, across simplex channel 122 to wirelesscommunications device 100 from server 112. Simplex channel 122 is usedfor downlink communication to communications device 100. When a userinitiates a data session, the user sends a request to server 112 acrossduplex channel 120 through carrier antenna 110. Scheduler 114, incommunication with server 112, sets the timing and frequency for whicheach of the requested data packets is sent. With the timing andfrequency set, scheduler 114 builds a schedule. Server 112 transmits theschedule built to communications device 100 through duplex channel 120.Server 112 communicates the data to carrier antenna 110 as well assecondary antenna 116, based upon the schedule. Duplex channel 120 sendssome of the data to communications device 100 as secondary antenna 116sends other parts of the data over simplex channel 122, which utilizedifferent frequencies.

According to this embodiment, a channel within the 1900 MHz frequencyband is used for most communication since it is the duplex or anchorchannel. Another channel, within the 850 MHz frequency band, is used asa simplex channel. Since many cellular towers already use thesefrequencies the current hardware can be utilized to implement thisembodiment. However, simplex channels that are licensed for downlinkonly can also be used to supplement the duplex channel since uplink isonly required on one channel.

In further embodiments of the present invention, simplex channels mayinstead be used in the uplink direction. Users with high volumes of datathat need to be uploaded use the simplex channels to send data to theserver. This may require the use of different frequencies for uplink anddownlink because there are some frequencies that are only licensed forone or the other.

In other exemplary embodiments, using for example, the system presentedin FIG. 1, a method includes the selection and reselection of anchorcarriers based upon signal strength and/or load. For example, certainanchor carriers are selected depending on particular loads presented inthe system at the time of transmission of information. Selection of suchanchor carriers is therefore dynamic and may be continually changed andmonitored depending on system status and conditions. The method used forsuch selection/reselection is substantially similar to that shown in thefigures.

FIG. 2A shows the individual data streams that allow asymmetricalcommunication between communications devices 200A and 200B and server212 though primary/anchor (or duplex) channel 210 and secondary channel216 according to an exemplary embodiment of the present invention. Asshown in FIG. 2A and in more detail in FIG. 2B, at the near-field 231,communication with communications device 200B occurs using a channel 220in the 1900 MHz frequency band as the duplex channel. Conversely, at afar-field 232, communication with communications device 200A occursusing channel 222 in the 850 MHz frequency band. For additional downlinkspeed in the near-field 231, a simplex channel 222E is used. Channel 220breaks down into four parts. Channel 220A is a payload uplink wherecommunications device 200B sends information to the server such asrequests for content, outgoing email, etc. Channel 220B is a payloaddownlink where communications device 200B receives internet content,incoming email, etc. Channel 220B is the main gateway for receiving dataon communications device 200B, and is the pipeline that needsbroadening. Channel 222E is another downlink that effectively doublesthe bandwidth in the downlink direction when combined with Channel 220B.However, in order to receive data on both channels 220B and 222E, aschedule must be transmitted by server 212 to communications device200B. Channels 220C and 220D serve as bidirectional control plain uplinkand downlink, respectively, solely for this schedule. The schedule isreceived by communications device 200B through channel 220D. Once thepackets of data from the schedule have been received by communicationsdevice 200B, confirmation of the reception is sent through channel 220C.

Due to a current limit in the power of the 1900 MHz antenna the sameconfiguration may not be possible in the far field. Another exemplaryembodiment uses a channel within the 850 MHz frequency band for theanchor channel, while a channel within the 1900 MHz frequency band isused for downlink only. Similar to the last example, channel 222 breaksdown into four parts. Channel 222A is a payload uplink wherecommunications device 200A sends information to the server such asrequests for content, outgoing email, etc. Channel 222B is a payloaddownlink where communications device 200A receives internet content,incoming email, etc. Channel 222B is the main gateway for receiving dataon communications device 200A, and is the pipeline that needsbroadening. Channel 220E is another downlink that effectively doublesthe bandwidth in the downlink direction when combined with Channel 222B.However, in order to receive data on both channels 222B and 220E, aschedule must be transmitted by server 212 to communications device200A. Channels 222C and 222D serve as bidirectional control plain uplinkand downlink, respectively, solely for this schedule. The schedule isreceived by communications device 200A through channel 222D. Once thepackets of data from the schedule have been received by communicationsdevice 200A, confirmation of the reception is sent through channel 222C.

FIGS. 3A and 3B show a communications device for use with asymmetricaldata transmission, according to an exemplary embodiment of the presentinvention.

FIG. 3A shows a front view of a communications device 300 for use withasymmetrical data transmission, according to an exemplary embodiment ofthe present invention. In this embodiment, the front of communicationsdevice 300 comprises a housing 304, a display 302, and a keypad 306.Housing 304 is preferably composed of a rigid and durable material, suchas plastic or metal, to hold the components in place and prevent thecomponents from being damaged. Display 302 is coupled to housing 304 andis used to view communications device 300′s outputs. In exemplaryembodiments of the present invention, display 302 is a liquid crystaldisplay (LCD). Keypad 306 allows a user to input numbers, input letters,select functions, play games, etc.

FIG. 3B shows a view of components of communications device 300,according to an exemplary embodiment of the present invention. In thisembodiment, the components comprise a memory unit 332, a processor 338,a transceiver module 336, a power source 330, and a descheduler 334 onmemory unit 332. Memory unit 332 stores an operating system forcommunications device 300. Memory unit 332 additionally stores photos,music, games, telephone settings, telephone numbers, etc. Transceivermodule 336 is utilized to communicate with wireless networks. Thiscommunication may use a cellular Radio Frequency (RF) connection,BLUETOOTH connection, WiFi connection, etc. Processor 338 runs theoperating system of communications device 300 as well as other featuresand programs. Power source 330 provides power to each of the componentsof communications device 300. Many different channels are sending tocommunications device 300 over varying frequencies. Descheduler 334pieces together the data from the multiple channels received bycommunications device 300. This is accomplished with the use of aschedule provided by a scheduler through an anchor channel.

FIG. 4 shows a flowchart of a method of asymmetrical transmission,according to an exemplary embodiment of the present invention. Thedotted line in the figure divides the tasks performed by the basestation/server from the tasks performed by the communications device.The tasks performed by the communications device are on the right of thedotted line while the tasks performed by the base station/server are onthe left side of the dotted line. In this embodiment, a user deviceconnects to an anchor channel 440, which is a duplex channel. Throughthis anchor channel, the communications device sends a data request 441to download data. A server receives the data request 442 from thecommunications device. The server determines whether there is ademanding application 443 that requires additional data flow for theanchor channel. If the data would not cause an overload to the anchorchannel, the data is scheduled 447 and subsequently sent 448A to thecommunications device. However, if the data would overload thefrequency, asymmetrical transmission is used. The base station/serverdistributes the requested data between the anchor channel and one ormore simplex channels 444. A scheduler onboard the server sends aschedule 445 to the communications device, describing the data packetsbeing sent and which channel they will arrive on, the anchor channel ora simplex channel. The schedule is received 446 by the communicationsdevice. Once the schedule is received, the server schedules the data447B according to that determined by the scheduler in step 445, and thensends the data via numerous paths 448B and 448C. Data that is carried onthe anchor channel is sent to the device through path 448B and datacarrier on non-anchor channel is sent to the device through path 448C.All data is received 449 by the communications device over the variouschannels. If the data has been received across multiple flow channels450 then the communications device needs to combine the data packets inthe order specified in the schedule 451. Otherwise, data that has beentransported through a single channel is received without need forfurther combination with other data.

In other embodiments of the process shown in FIG. 4, distribution isused more frequently. Rather than only use data distribution when achannel is overloaded, the process uses data distribution when theresult is more optimal than without distribution. If the datatransmission can be received by the communications device faster, moreefficiently and/or less costly using distribution than without, then theprocess uses distribution regardless of whether or not the channel isoverloaded. If the distance between the communications device and thebase station is far, then most likely 850 MHz channels are used, and ifthe distance is near, then either 850 MHz or 1900 MHz channels are useddepending on signal strength and network load. Sometimes multiplesimplex channels are used to further distribute the data. Furtherembodiments calculate which and how many simplex channels to use totransmit the data to the communications device the fastest.

FIG. 5 shows a data schedule 518 used by a scheduler in communicationwith a server, according to an exemplary embodiment of the presentinvention. In this embodiment, a bit number 560 is correlated with asize 562 and a channel 564. When a user requests a download, thescheduler divides up the requested data into bit numbers 560. Bitnumbers 560 are then distributed among channels on which the serversends them. Schedule 518 shows which bit number 560 is sent on eachchannel 564, along with size 562 of each bit number 560. Schedule 518 issent to the communications device, giving the communications device aroadmap to the data about to be sent. Once the schedule is received thecommunications device starts listening on other channels. According tothis schedule, the communications device knows that the first 512 bitsof data on the 850 MHz channel make up bit number 0001. Meanwhile, thefirst 1024 bits of data on the 1900 MHz channel make up bit number 0003.This continues across all channels until all the bits of data arecollected. Once the communications device collects all the bits of data,a descheduler onboard the communications device pieces together the bitsof data according to schedule 518.

FIG. 6 shows a system utilizing asymmetrical data transmission andreception, utilizing multiple simplex channels, according to anexemplary embodiment of the present invention. Communications device 600communicates using channel 620 as the anchor channel. When the demandfrom communications device 600 exceeds the bandwidth through channel620, other channels are used along with channel 620. Channel 622 can beused to supplement the downlink of channel 620, but sometimes the demandfrom communications device 600 can exceed the combined bandwidth ofchannels 620 and 622. When this happens channel 621 and channel 623,which are also simplex, downlink only, channels, are used to furthersupplement the downlink of channels 620 and 622.

Even more downlink channels can be used alongside an anchor channel tosupplement the downlink, or alternatively the uplink direction of acommunications device.

The foregoing disclosure of the exemplary embodiments of the presentinvention has been presented for purposes of illustration anddescription. It is not intended to be exhaustive or to limit theinvention to the precise forms disclosed. Many variations andmodifications of the embodiments described herein will be apparent toone of ordinary skill in the art in light of the above disclosure. Thescope of the invention is to be defined only by the claims appendedhereto, and by their equivalents.

Further, in describing representative embodiments of the presentinvention, the specification may have presented the method and/orprocess of the present invention as a particular sequence of steps.However, to the extent that the method or process does not rely on theparticular order of steps set forth herein, the method or process shouldnot be limited to the particular sequence of steps described. As one ofordinary skill in the art would appreciate, other sequences of steps maybe possible. Therefore, the particular order of the steps set forth inthe specification should not be construed as limitations on the claims.In addition, the claims directed to the method and/or process of thepresent invention should not be limited to the performance of theirsteps in the order written, and one skilled in the art can readilyappreciate that the sequences may be varied and still remain within thespirit and scope of the present invention.

1-20. (canceled)
 21. A method, comprising: receiving, by a systemcomprising at least one processor, a schedule indicative of adistribution of a set of data packets between an anchor channel,utilized for duplex transmission, and a simplex channel, utilized forsimplex transmission; receiving, by the system, the set of data packetsvia the anchor channel and the simplex channel, based on the schedule;and organizing, by the system, the set of data packets, wherein theorganizing the set of data packets facilitates communication between atleast one network server and the system.
 22. The method of claim 21,wherein the receiving the set of data packets includes: receiving afirst portion of the set of data packets via the anchor channel; andreceiving a second portion of the set of data packets via the simplexchannel.
 23. The method of claim 22, wherein the receiving the scheduleincludes receiving the schedule prior to receiving the first portion ofthe set of data packets and the second portion of the set of datapackets.
 24. The method of claim 21, further comprising: identifying, bythe system, a channel on which a portion of the set of data packets isto be received at a specified time, based on the schedule.
 25. Themethod of claim 21, wherein the receiving the schedule includesreceiving timing information associated with receipt of the set of datapackets.
 26. The method of claim 21, wherein the receiving the scheduleincludes receiving frequency information associated with receipt of theset of data packets.
 27. The method of claim 21, further comprising:transmitting, by the system, a request for the set of data packets viathe anchor channel.
 28. The method of claim 21, wherein the distributionof the set of data packets is a first distribution of a first set ofdata packets, and the method further comprises: transmitting, by thesystem, feedback information, associated with the set of data packets,that is utilized to balance a second distribution of a second set ofdata packets between the anchor channel and the simplex channel.
 29. Themethod of claim 21, further comprising: selecting, by the system, a setof frequencies associated with the anchor channel based in part on adistance between the system and an access point.
 30. A system,comprising: at least one memory that stores computer-executableinstructions; at least one processor, communicatively coupled to the atleast one memory, that facilitates execution of the computer-executableinstructions that at least: obtain a schedule indicative of adistribution of data packets between an anchor channel, utilized forduplex transmission, and a simplex channel, utilized for simplextransmission, and receive the data packets via the anchor channel andthe simplex channel, based on the schedule; and aggregate the datapackets, based on the schedule, to facilitate communication between atleast one network server and the system.
 31. The system of claim 30,wherein the at least one processor further facilitates the execution ofthe computer-executable instructions to determine a channel on which aportion of the data packets are to be received during a specified timerange, based on the schedule.
 32. The system of claim 31, wherein the atleast one processor further facilitates the execution of thecomputer-executable instructions to receive the portion of the datapackets on the channel during the specified time range.
 33. The systemof claim 30, wherein the at least one processor further facilitates theexecution of the computer-executable instructions to receive theschedule via the anchor channel.
 34. The system of claim 30, wherein thedistribution of the data packets is a first distribution of first datapackets, and the at least one processor further facilitates theexecution of the computer-executable instructions to generate feedbackinformation associated with receipt of the first data packets, andwherein the feedback information is utilized to balance a seconddistribution of second data packets between the anchor channel and thesimplex channel.
 35. A non-transitory computer-readable storage mediumcomprising computer-executable instructions that, in response toexecution, cause a system, including at least one processor, to performoperations comprising: receiving a schedule indicative of a distributionof data between an anchor channel, utilized for duplex transmission, anda simplex channel, utilized for simplex transmission; receiving the datareceived via the anchor channel and the simplex channel, based on theschedule; and aggregating the data, based on the schedule, to facilitatecommunication between at least one network server and the system. 36.The non-transitory computer-readable storage medium of claim 35, whereinthe operations further comprise: identifying a channel on which aportion of the data is to be received during a specified time range,based on the schedule.
 37. The non-transitory computer-readable storagemedium of claim 36, wherein the operations further comprise: listeningon the channel during the specified time range.
 38. The non-transitorycomputer-readable storage medium of claim 35, wherein the operationsfurther comprise: selecting a set of frequencies associated with theanchor channel based in part on a distance between the system and anaccess point.
 39. The non-transitory computer-readable storage medium ofclaim 35, wherein the operations further comprise: selecting a set offrequencies associated with the simplex channel based in part on adistance between the system and an access point.
 40. The non-transitorycomputer-readable storage medium of claim 35, wherein the operationsfurther comprise: transmitting, by the system, a request for the datavia the anchor channel.